Method and apparatus for producing fabrics of high quality with considerably enhanced productivity

ABSTRACT

A method and apparatus for carrying out an automatic inspection of fabric quality concurrently with an advancing weaving operation by detecting the formed defect, memorizing the detected results with clear distinction as to kind, total number, formation rate and degree of the defects formed on the fabric, comparing thusly detected results with previously given data and, only when the result is not desirable, stopping the operation of the loom. Memorized results can be used for locating the formed defects in a subsequent defect retrieving process.

United States Patent METHOD AND APPARATUS FOR PRODUCING FABRICS OF HIGH QUALITY WITH CONSIDERABLY ENHANCED PRODUCTIVITY 15 Claims, 3 Drawing Figs.

U.S. Cl 139/348, 66/166, 139/336 Int. Cl 003d 51/18 Field of Search 139/1, 336,

References Cited UNITED STATES PATENTS 3,116,621 1/1964 Klein et al 66/166 3,276,227 10/1966 Althaus et a1. 139/348 3,409,779 11/1968 Fertig 66/166 3,459,235 8/1969 Cauthen et al 139/1 FOREIGN PATENTS 1,515,876 7/1966 France 139/336 Primary Examiner-Henry S. Jaudon Atlorneys- Robert E. Burns and Emmanuel J. Lobato WEAVING e RECORDING LooM ELEMENT MEl/ORY ELEMENT 5 3 OPERATIONAL -TERMINAL 4 s 8i 1 LENGTH "COMPARATOR DETECTING ELEMENT 7 INFORMATION SOURCE PATENTEUUCT 19 I9 sum 20F 2 3.613.743

METHOD AND APPARATUS FOR PRODUCING FABRICS OF HIGH QUALITY WITH CONSIDERABLY ENHANCED PRODUCTIVITY The present invention relates to an improved method and apparatus for producing fabrics of high quality with considerably enhanced productivity and, more particularly, to an improved method and apparatus for automatically carrying out quality inspection of fabric concurrently with the advance ment of the weaving operation so as to reduce the production of fabrics having an excessive number of defects.

As is well known, there is a great demand for woven fabrics of extremely high quality and, in order to meet with such expanding demand, it has become increasingly necessary to produce fabrics of extremely high quality with enhanced production efiiciency. One of the key factors for achieving this exists in carrying out the fabric inspection process in such a manner that the inspected results are instantly reflected upon the weaving control, that is the fabric inspection process is carried out concurrently and in correlation with the advancement of the weaving process.

Usually, the quality of the woven fabric is classified into three grades; A-grade, B-grade and C-grade. Classification of the fabrics quality into the listed classes, among which a fabric of A-grade is provided with highest quality, is determined in view of the number, kind and degree of defects found on a surface of a fabric of a unit length.

In the conventional method of evaluating the fabric quality, the woven fabric is taken from the weaving loom and subjected to an eyesight inspection or an optical mechanical inspection process on a suitable inspection machine. This means that the inspection process is performed in a manner or stage separated from the weaving process.

This conventional fabric-inspecting process is accompanied with several drawbacks. For example, once a serious defect is caused during the weaving process, that defect is accumulated as the weaving process proceeds, and the formation of such defects cannot be precisely and exactly detected until the fabric is brought to the inspection process. That is, a succcessive formation of such defect cannot be obviated effectively and quickly. This causes undesirable successive production of fabrics of degraded quality and is a fatal disadvantage from a view point of economy in the fabric production. Further, as the inspection of the fabric is done subsequent to the weaving process of that fabric, it becomes rather difficult to relate the detected deflects to the malfunctions in the weaving operation, which malfunction might have caused the formation of those defects. This tends to lead to a delayed loom maintenance necessary for eliminating the cause of such malfunctions and to introduce further successive production of fabrics having defects caused by such malfunctions. Moreover, in the conventional weaving process, the warp sheet is provided with cut marks, for showing a unit length of the woven fabric, during the weaving preparation process and the resultant quality of the produced fabric is evaluated in view of thusly marked unit lengths of the fabric. Therefore, even in case a fabric portion of extremely high quality extends from a unit length to a next unit length crossing over the cut-mark point, the fabrics of both unit lengths will be classified as fabrics of degraded I quality if the remaining length portions in both fabrics are provided with an excessive number ofdefects.

A principal object of the present invention is to provide an improved method and apparatus for carrying out an inspection of fabric quality concurrently with an advancing weaving process in a manner to instantly and effectively reflect the detected results, thereby permitting a prompt elimination of the causes of such defects.

Another object of the present invention is to provide an improved method and apparatus for achieving production of highly graded fabrics at high-production efficiency while effectively eliminating drawbacks encountered in the prior art.

A further object of the present invention is to provide an improved method and apparatus for bringing about an effective. economical and exact repairing of the formed defects after the completion of the weaving.

A still further object of the present invention is to provide an improved method and apparatus effectively used for enhancing the yield of A-grade fabrics in the fabric formation.

In the following description, a term "count of defect will be often times used. This term should be understood as a combined conception of the kind and degree of the formed defects. Therefore, the term total count of defect refers to a combined conception of kind of defects with degree and number of the formed defect within a unit length of the fabric evaluated. Thus, when the degree of the formed defect is too high, the resultant total count of defects may be large as compared to the number of defects per a unit length of the fabric, and for various kinds of defects, certain plural unit counts are correspondingly given as to a single defect.

Now, in order to achieve the above-described objects ofthe invention, in the inspecting system of the present invention, counts of defects formed on the fabric being woven are detected in an optical manner and the results are successively and cumulatively brought into a memory in synchronism with memorization of the weaving length of the fabric. Thusly memorized results are compared with previously given standard data of the allowable total count of defects. In this memorization and comparison of the detected results, not only the accumulated total count of defects, but also a rate of defect formation and kind of the detected results are distinguished. When the memorized total count of defects exceeds on allowable limit or the rate of defect formation becomes too high, the weaving operation is automatically stopped and an alarm for calling the operators attention will be given. The memorized results of the defects formation should be recorded in a suitable manner so as to permit an easy and quick location of the defects on the fabric after weaving and in the subsequent defect retrieving process.

Further features and advantages of the present invention will be made more apparent in the following description with reference to the attached drawings, wherein FIG. 1 is a block diagram view of an arrangement of the apparatus of the present invention,

FIG. 2 is also a diagrammatic view for showing an embodiment of the apparatus shown in FIG. 1, and

FIG. 3 is an explanatory perspective view for showing a portion of an actual arrangement of the apparatus shown in FIG. 2.

Referring to FIG. I, the arrangement of the apparatus of the present invention is shown in a summarized illustration. In the arrangement, defects formed on the fabric processed on a weaving loom l are successively detected by an optical-type detecting element 2 and luminous signals corresponding to the detected defects are converted into corresponding electric signals so as to be brought into a memory 3. This memorization of the detected results by the memory 3 includes three simultaneously proceeding operations. In the first operation, the number of the defects formed is memorized in an accumulative manner. In the second operation, the rate of the defects formation is memorized and in the third operation, the kind and type of the formed defects are memorized.

Concurrently with the above-described defect detection and memorization, the length of the woven fabric is also sensed, successively, by a detecting element 4, and periodic signals corresponding to the detected woven length are converted into corresponding periodic electric signals so as to be brought into the memory 3 for memorization.

The output of the memory 3 is next brought into a comparator element 6 connected to the memory 3 and compared with informational data brought thereinto from a reference information source 7. This comparison is performed as to the total count of defects per unit length of the fabric, the rate of defect formation and kind and type of the formed defects. When the total count of defects exceeds the allowable limit or the rate of defect formation becomes abnormal, then the comparator element 6 issues signals actuating an operational terminal 8 whose function will be explained later in detail. The output of the memory 3 is also brought into a recording element 9 and the recorded results are used for locating the defecting portion on the fabric in the subsequent defects retrieving process.

Referring to FIGS. 2 and 3, an embodiment of the apparatus shown in FIG. 1 is illustrated.

In the illustrated arrangement, a warp sheet 11 is shed by healds 12a and 12b, weft yarn is inserted into the opened shed, a reed 13 beats the inserted weftto a cloth fell of a woven fabric 14 and the woven fabric 14 is taken up by a surface roller 16 in a manner the same with the conventional weaving technique. In combination with the above-described arrangement, a detecting terminal 17 of the present invention includes a light source 18 extending over an entire width of the fabric 14 for radiating light towards the fabric 14 from an underside direction and a light receiver 19 disposed in an arrangement receptive of light reflected from the fabric 14. Provided that the light source 18 radiates light of a constant luminous quantity per unit length of time and the weaving operation is advanced at a constant rate, the presence of defects on the fabric naturally causes variations in the quantity of light received by the light receiver 19. The received luminous quantity is converted into corresponding electric signals by a photoelectric converter 21, and the photoelectric converter 21 generates pulses only when the received luminous quantity varies due to detection of the defects on the fabric 14. The generated pulses are brought into a pulse motor 22 of the memory 3, which motor is connected to the photoelectric converter 21 and rotatable by a predesigned rotational angle upon receipt of the pulses. The composition of the detecting terminal 17 is not limited only to the abovedescribed arrangement. For example, a luminous scanning method can advantageously be employed. Also, a more detailed version of the detecting terminal is disclosed for example in US. Pat. No. 3,1 16,621.

Aside from the abovedescribed arrangement of the defects detecting element 2, the woven length-detecting element 4 in cludes a woven length-detecting terminal 23 and a photoelectric converter 24 connected thereto. The woven length detecting terminal 23 includes a disc 26 axially secured on a rotational shaft 27 of the surface roller 16. This disc 26 is provided with a plurality of radially formed apertures 28 of a concentric disposition. Sandwiching the disc 26 in a spaced relationship, a light source 29 and a light receiver 31 are disposed in a facing disposition, both members being stationary to the framework of the loom (not shown). The light source 29 always radiates a light of a constant luminous quantity towards the light receiver 31. However, as the disc 26 rotates, following rotation of the surface roller 16, reception of the light by the light receiver 31 is intercepted periodically and accordingly, the quantity of light received by the light receiver 31 varies in synchronism with increase in the woven length of the fabric 14. This variation in the received luminous qUantity is converted into corresponding electric pulses by the photoelectric converter 24 and these pulses are next fed to a pulse motor 32 of the memory 3, such motor 32 being rotatable by a predesigned rotational angle upon receipt of the pulses.

The memory 3 further includes a dial plate 33, a length indicator 34 centrally and rotationally disposed to the dial plate 33, a defect indicator 36 centrally disposed to the dial plate 33 in a coaxial arrangement with the length indicator 34. Rotation of the defect indicator 36 is actuated by the pulse motor 22 independently from that of the length indicator 34 actuated by the pulse motor 32. In combination with the above-listed indicators 34 and 36, a stationary abutment 37 is disposed on the dial plate 33. The dial plate 33 is provided with two sets of scale marks, the outer marks being used for the length indicator 34 and the inner marks being used for the defect indicator 36.

In the above-described arrangement, both of the indicators 34 and 36 are rotated by predesigned rotational angles, in counterclockwise direction in the drawing, upon receipt of the respective pulses so as to memorize the count of defects and the length of the woven fabric in accumulative manners. In the dial arrangement, the angular phase difference 0, between the starting angular positions of the length indicator 34 and the stationary abutment 37 is selected so as to correspond to a length of one piece fabric. When the length indicator 34 contacts the stationary abutment 37, a device for marking the cut mark on the fabric is actuated and the indicators 34 and 36 are both returned to their initial starting positions. The initial starting position of the defect indicator 36 is behind that of the length indicator 34 by an angular phase difference 0 which difference corresponds to a total allowable count of defects per one-piece length of the fabric. When the defect indicator 36 contacts the length indicator 34 during their counterclockwise rotation, the memory 3 issues an instruction signal to the comparator element 6.

The comparator element 6 is previously provided with informational data from the reference information source 7 con nected thereto, which informational data concerns the kind and the type of the defects and rate of defect formation. Using thusly provided informational data, the comparator element 6 has a function of distinguishing if the formed defects are repairable in the subsequent defects-retrieving process. Even when the detected total count of defects is so great that the resultant fabric cannot be classified into A-grade, the comparator element 6 does not issue signals for stopping the loom if the detected defects are distinguished as easily repairable in the subsequent defects-retrieving process. Owing to this distinguishing faculty of the comparator element 6, the productivity of the loom can be enhanced considerably. In case the accumulated count of defects exceed the allowable limit and the defects are distinguished as hardly repairable in the subsequent defects-retrieving process, the comparator element 6 issues signals actuating the operational terminal 8, which terminal includes a mechanism 38 for effecting the running of the loom, a mechanism 39 for effecting marking the cut mark on the fabric, a mechanism 41 for turning on and off the alarm lamp for operators and a mechanism 42 for returning the indicators 34 and 36 to their initial starting positions. For example, each such mechanism may include a relay for effecting electrical control, or a solenoid device for effecting mechanical control.

Further, as is already mentioned, the comparator element 6 is provided with a faculty of distinguishing the rate of defect formation and receiving reference informational data of this kind from the reference information source 7. Therefore, even if the accumulated count of defects do not reach the allowable limit, the comparator element 6 issues signals for actuating the operational terminal 8 when an extraordinarily high rate of defeet formation is recognized. Owing to this distinguishing faculty of the comparator element 6, an adequate maintenance can be applied to the loom so as to eliminate the causes of such defect formation, thereby resulting in an increase in the yield of A-grade fabrics.

Independent from the above-described operation of the comparator element 6, the recording element 9 is connected to the output terminal of the memory 3 so as to record the results accumulatively memorized by the memory 3. For example, a recording tape may be used for this purpose. This recording tape is then brought to the subsequent fabric inspection and defect-retrieving process and used for automatically locating the defected portion of the fabric.

What we claim is:

l. A method for producing fabrics of high quality with considerably enhanced productivity on a weaving loom comprising the steps of detecting counts of fabric defects by optical means, converting thusly detected counts of defects into corresponding electric defect signals, memorizing said electric defect signals in an accumulative manner, simultaneously detecting woven length measurements of said fabric by optical means, converting said detected length measurements into corresponding length signals, memorizing said electric length signals in an accumulative manner, comparing said accumulatively memorized defect signals and length signals with given reference information data, and generating instruction signals operative on said weaving loom when said accumulatively memorized total count of defects exceeds an allowable limit in proportion to said reference data.

2. A method as set forth in claim 1, further comprising recording said accumulatively memorized defect signals and length signals so as to use them for locating defective portions on said fabric in a subsequent defect retrieving process.

3. A method as set forth in claim 1, wherein said comparison is made as to the total count of defects per unit length of said fabric, as to the rate of defect formation per unit duration of weaving time, and as to the kind and type of said defects.

4. A method as set forth in claim 1, further comprising distinguishing said memorized defect signals as to their repairability in a subsequent defect retrieving process.

5. An apparatus for producing fabrics of high quality with considerably enhanced productivity on a weaving loom comprising, in combination, defect-detecting means disposed in the vicinity of a fabric being woven on said loom for detecting the presence of defects on said fabric, length-detecting means disposed in relation to a fabric takeup mechanism of said loom for detecting unit woven lengths of said fabric, memory means receptive of output signals of said two detecting means so as to memorize said signals in an accumulative manner, comparator means receptive of output signals from said memory, a reference information source connnected to said comparator means for supplying informational reference data to said comparator means, said comparator means being for generating instruction signals in response to said memory means and reference information signals, and operational means receptive of said instruction signals from said comparator means for controlling said loom; said comparator element generating said instruction signals when said accumulatively memorized count of defects exceeds an allowable limit.

6. An apparatus as set forth in claim 5, further comprising a recording element receptive of said memory means output signals for recording counts of defects in relation to said woven lengths of said fabric.

7. An apparatus as set forth in claim 5, wherein said defectdetecting means includes a luminous-type defect-detecting device and a photoelectric converter for converting detected luminous defect signals into corresponding electric defect signals.

8. An apparatus as set forth in claim 7, wherein said defectdetecting device includes a light source for radiating light of a constant luminous quantity towards said fabric and a light receiver receptive of light reflected from said fabric.

9. An apparatus as set forth in claim 8, wherein said light source extends over an entire width of said fabric.

10. An apparatus as set forth in claim 8, wherein said light source scans over an entire width of said fabric.

11. An apparatus as set forth in claim 5 wherein said lengthdetecting means includes a luminous length-detecting means for generating luminous length signals, and a photoelectric converter for converting said luminous length signals into corresponding electric length signals.

12. An apparatus as set forth in claim 7, wherein said length-detecting means includes a rotational shaft of a surface roller of said loom, and a disc secured to said shaft and provided with a plurality of concentrically formed apertures, a stationary light source spacedly disposed on one side of said disc and radiating light of a constant luminous quantity, and a light receiver spacedly positioned on another side of said disc in an arrangement receptive of light arriving thereto through said apertures of said disc.

13. An apparatus as set forth in claim 5, wherein said memory includes a first pulse motor rotational by a predetermined rotational angle upon receipt of output signals of said defect-detecting means, a defect indicator rotated by said pulse motor, a second pulse motor rotational by a predetermined rotational angle upon receipt of output signals of said woven length-detecting means, a length indicator rotated by said second pulse motor, a dial discon which said two indicators are centrally, rotationally and coaxially disposed, and an abutment for stopping rotation of said indicators.

14. An apparatus as set forth in claim 5, wherein said comparator means is provided with means for distinguishing if said formed defects are repairable in a subsequent defect-retriev ing process.

15. An apparatus claimed in claim 5, wherein said operational means includes a mechanism for controlling the running of said loom, a mechanism for controlling the marking of cut marks on said fabric, a mechanism for controlling an alarm lamp, and a mechanism for controlling the returning of the disposition of said memory to an initial position. 

1. A method for producing fabrics of high quality with considerably enhanced productivity on a weaving loom comprising the steps of detecting counts of fabric defects by optical means, converting thusly detected counts of defects into corresponding electric defect signals, memorizing said electric defect signals in an accumulative manner, simultaneously detecting woven length measurements of said fabric by optical means, converting said detected length measurements into corresponding length signals, memorizing said electric length signals in an accumulative manner, comparing said accumulatively memorized defect signals and length signals with given reference information data, and generating instruction signals operative on said weaving loom when said accumulatively memorized total count of defects exceeds an allowable limit in proportion to said reference data.
 2. A method as set forth in claim 1, further comprising recording said accumulatively memorized defect signals and length signals so as to use them for locating defective portions on said fabric in a subsequent defect retrieving process.
 3. A method as set forth in claim 1, wherein said comparison is made as to the total count of defects per unit length of said fabric, as to the rate of defect formation per unit duration of weaving time, and as to the kind and type of said defects.
 4. A method as set forth in claim 1, further comprising distinguishing said memorized defect signals as to their repairability in a subsequent defect retrieving process.
 5. An apparatus for producing fabrics of high quality with considerably enhanced productivity on a weaving loom comprising, in combination, defect-detecting means disposed in the vicinity of a fabric being woven on said loom for detecting the presence of defects on said fabric, length-detecting means disposed in relation to a fabric takeup mechanism of said loom for detecting unit woven lengths of said fabric, memory means receptive of output signals of said two detecting means so as to memorize said signals in an accumulative manner, comparator means receptive of output signals from said memory, a reference information source connnected to said comparator means for supplying informational reference data to said comparator means, said comparator means being for generating instruction signals in response to said memory means and reference information signals, and operational means receptive of said instruction signals fRom said comparator means for controlling said loom; said comparator element generating said instruction signals when said accumulatively memorized count of defects exceeds an allowable limit.
 6. An apparatus as set forth in claim 5, further comprising a recording element receptive of said memory means output signals for recording counts of defects in relation to said woven lengths of said fabric.
 7. An apparatus as set forth in claim 5, wherein said defect-detecting means includes a luminous-type defect-detecting device and a photoelectric converter for converting detected luminous defect signals into corresponding electric defect signals.
 8. An apparatus as set forth in claim 7, wherein said defect-detecting device includes a light source for radiating light of a constant luminous quantity towards said fabric and a light receiver receptive of light reflected from said fabric.
 9. An apparatus as set forth in claim 8, wherein said light source extends over an entire width of said fabric.
 10. An apparatus as set forth in claim 8, wherein said light source scans over an entire width of said fabric.
 11. An apparatus as set forth in claim 5 wherein said length-detecting means includes a luminous length-detecting means for generating luminous length signals, and a photoelectric converter for converting said luminous length signals into corresponding electric length signals.
 12. An apparatus as set forth in claim 7, wherein said length-detecting means includes a rotational shaft of a surface roller of said loom, and a disc secured to said shaft and provided with a plurality of concentrically formed apertures, a stationary light source spacedly disposed on one side of said disc and radiating light of a constant luminous quantity, and a light receiver spacedly positioned on another side of said disc in an arrangement receptive of light arriving thereto through said apertures of said disc.
 13. An apparatus as set forth in claim 5, wherein said memory includes a first pulse motor rotational by a predetermined rotational angle upon receipt of output signals of said defect-detecting means, a defect indicator rotated by said pulse motor, a second pulse motor rotational by a predetermined rotational angle upon receipt of output signals of said woven length-detecting means, a length indicator rotated by said second pulse motor, a dial discon which said two indicators are centrally, rotationally and coaxially disposed, and an abutment for stopping rotation of said indicators.
 14. An apparatus as set forth in claim 5, wherein said comparator means is provided with means for distinguishing if said formed defects are repairable in a subsequent defect-retrieving process.
 15. An apparatus claimed in claim 5, wherein said operational means includes a mechanism for controlling the running of said loom, a mechanism for controlling the marking of cut marks on said fabric, a mechanism for controlling an alarm lamp, and a mechanism for controlling the returning of the disposition of said memory to an initial position. 